This invention relates to automatic and semi-automatic seeders. More specifically, the invention relates to a seeder for use in the bedding plant industry which will reliably pick up seeds from a seed tray and deposit them in a predetermined array into a flat or into peat cups.
The problem of getting millions of seedlings planted in a short period of time has forced the horticultural nursery industry into mechanizing this operation. Horticulturists have recognized that direct seeding by machine can greatly cut labor costs in the initial planting of the seeds. By initially planting the seeds in individual peat cups, the step of transplanting the plants from flats to peat cups is eliminated. Thus, there is no setback in growth due to transplanting, and the plants are not contaminated by the handling associated with transplanting.
U.S. Pat. No. 2,546,838 to Carl H. Tasche describes a seeder with a suction header which has a coordinate array of downwardly projecting suction tubes. Upon producing a suction in the header, the tubes pick up seeds from a seed tray. The header is then slidably moved on a horizontal track to a position over a flat where the suction is cut off and the tubes deposit the seeds in a coordinate array. U.S. Pat. No. 2,445,701 describes a seed counting machine using a similar principle.
Jiffy Products of America of West Chicago, Illinois, sells a Fricke-Jiffy Seeder which is designed to pick up and distribute through an arrangement of tubes of maximum of 96 seeds into a large flat. The Fricke-Jiffy Seeder is described in an article in the September 1970 issue of Grower Talks magazine published by Geo. J. Ball, Inc., of West Chicago, Illinois 60185.
The previously described prior art devices incorporate hollow suction tubes which point downward and are mechanically lowered into the seed tray to pick up seeds. It has been found that in normal operation, a certain percentage, around 10 percent, of the tubes will not pick up a seed in a given cycle. The operator has no way to visually inspect the ends of the tubes to determine whether each tube has picked up a seed. Furthermore, when the seed tray empties to less than one-half full, the seeds in the tray tend to pack into a hard layer and thus become much harder to pick up. Periodic refilling and stirring of the seeds is necessary to alleviate this problem. This packing phenomenon occurs most noticeably with "fuzzy" tomato seeds.
Thus, in this era of increasing labor cost, there is an acute need for an improved semi-automatic seeder for the small to medium sized nursery which allows essentially 100 percent pick up of seeds and which allows the operator to view each suction hole to assure that a seed has been picked up by each hole. Also, the seeder should be operable with a low level of seeds in the seed tray to prevent the unnecessary waste of unused seeds.
The prior art practice was improved upon and the previously mentioned objectives were accomplished by the subject matter of copending application, Ser. No. 573,412, which provides a seeding apparatus for transferring seeds from a seed supply to a flat or individual peat cups. This seeding apparatus incorporates a hand-manipulated seed pick-up head and a seed tray which holds the supply of seeds to be planted. The seed tray has a substantially flat bottom and interconnecting sides and is adapted to hold a predetermined supply of seeds. A vacuum source is connected to the pick-up head for providing a suction force through a horizontal line of equally-spaced apertures on the frontal face of the pick-up head. The apertures are smaller than the seeds so that the seeds are held in place over the apertures. These apertures are readily visible by the operator at all times so that he may check on the efficiency of operation, i.e., he can see which apertures have seeds and which do not. A manifold positioned adjacent to the seed tray of this apparatus provides a plurality of horizontally aligned and spaced openings along an upper surface. These openings are positioned and spaced so as to mate with the apertures on the face of the head so as to receive the seeds when released. An array of plastic tubes communicate with the openings and extend downwardly to deposit the seeds. A disadvantage of this apparatus is that the seeds sometimes stick to the frontal face of the pickup head when the vacuum is released. In this regard, it becomes an object of the present invention to provide means for assuring that all of the seeds secured to the frontal face are released when desired. Other objects, including a simpler means for positioning the tubes over the peat cups, will become apparent from the specification. Also, an improved valve is provided.
While applicant's copending application apparatus provides a much needed and greatly improved seeding apparatus, it becomes an object of the present invention to improve upon such apparatus while maintaining its many advantages.